1. Field of the Invention
The present invention relates to a method and apparatus for testing a telecommunication system and more particular, to detecting signals generated by a telecommunication system, such a as a voice processing system providing voicemail, or automated attendant, or interactive voice response, etc.; or an automatic call distributor; or a computer-telephone integration system; or command and control components of a switching system; or other networks and enhanced services provided via public or private switched telephone networks, to evaluate the operation, accuracy and quality of the telecommunication system, including machine produced voice signals generated by the system.
2. Description of the Related Art
For over a century, the public switched telephone network (PSTN) was used primarily to provide voice communication between two human beings using telephones. In the last quarter century or so the PSTN has increasingly been used to provide communication with or between machines, such as computers and facsimile machines. During the last decade and a half, use of the PSTN has expanded to include communication between human beings using telephones and machines which reproduce voice signals that have been previously recorded. The term telecommunication system will be used to refer to equipment which performs voice processing, such as voicemail, automated attendant, interactive voice response (IVR), etc. In addition, the term telecommunication system as used herein includes systems which provide computer-telephone integration (CTI), automatic call distribution (ACD) and many other functions in addition to the more traditional functions of telecommunication systems such as those provided by private branch exchanges (PBXs), central office (CO) equipment, etc.
Prior to the development of new telecommunication functions in the last two decades or so, telecommunication systems were primarily tested by establishing that a voice conversation could be carried from point A to point B. As a result, telecommunication systems have conventionally been tested to determine that connections are made properly and signal quality is satisfactory. While both proper connections and signal quality still need to be tested, the additional functions performed by many different types of telecommunication systems require that a much different type of testing be performed. Initially, human beings were used to test telecommunication systems having voice processing capability.
The assignee of the present invention introduced the Hammer.TM. testing and monitoring system in 1992. The Hammer.TM. system uses a personal computer with voice processing capability to execute "programs" written in a language similar to BASIC with extensions for control of the voice processing and telecommunication capabilities of the computer. The extensions include the ability to play prerecorded voice messages, generate dual tone multifrequency (DTMF) and multifrequency (MF) signals for controlling telecommunication systems, such as voicemail systems and switching systems in the PSTN, respectively. In addition, an RS-232 serial port provided in the Hammer.TM. system can transmit and receive out-of-band signals. As a result, the previously available Hammer.TM. system can be programmed to test a wide variety of functions provided by telecommunication systems. All that is required is initiation of a stored program by a human operator.
Despite the significant advancements of the Hammer.TM. system over the totally or near totally manual testing methods that were used before introduction of the Hammer.TM. system, there are several drawbacks to the previously available Hammer.TM. system. These drawbacks include the significant amount of time and knowledge required to prepare "programs" to perform automatic testing of telecommunication systems; the need to create each "program" prior to performing testing (batch processing only); the need for human beings to initiate execution of each "program"; and the need for human beings to evaluate the voice signals generated by telecommunication systems under test. No other known test system provided these features prior to the development of the present invention.